It would be easier to run a cable, like a bicycle brake cable, and maybe run it outside the exterior rail of the receiver, then just slips inside the forearm. If it could be done without modifing the upper receiver then the whole bullpup kit would just be the furniture, and any 93 upper could be made into a bullpup.

Yes, I love it! You can see the rod running along the side of the receiver into the forearm. It does not seem to hard to make, especialy using a tri rail forearm.

I see 3 problems with this setup. First it adds about 5"-6" to the LOP, second the gun would be very back heavy, third without that AR style carry handle you face is going to be right above the ejection port. But the cool factor outways all of that.